WatermarkingPart 2: Future

Work

Electrical and Computer Engineering DepartmentVillanova University

18 August 2004

Robert J.Berger II

Michael P.Marcinak

Bijan G.Mobasseri

Michael Marcinak

Watermarking Part 2: Future Work

•JPEG Watermarking Software

•Current Version

•Enhancements

•Additional Components

•Video Applications

•Error resiliency

•MPEG 1|2|4, H.263, H.264

Overview

Michael Marcinak

Watermarking Part 2: Future Work

•Goals:

•Produce a standalone package

•Incorporate visual masking

•Improve speed and efficiency

•Maximize capacity

JPEG Watermarking Software

Michael Marcinak

Watermarking Part 2: Future Work

Current Version: Encoder

Michael Marcinak

Watermarking Part 2: Future Work

Final Version: Encoder

Michael Marcinak

Watermarking Part 2: Future Work

•Watermarking maps used VLC’s to unused VLC’s with different run/size

•Run/size information of unused VLC’s must be modified in the Huffman table

Visual Masking

Michael Marcinak

Watermarking Part 2: Future Work

•Three scenarios of visual masking:

•watermarked VLC is longer than original

•watermarked VLC is shorter than original

•watermarked and original are the same length

Visual Masking

Michael Marcinak

Watermarking Part 2: Future Work

•Broaden scope from “lenaG.jpg”

•Grayscale and color images

•Potentially reduce file size

•Remove zero padds (0xff00) by watermarking 1’s to 0’s

Enhancements

Michael Marcinak

Watermarking Part 2: Future Work

•Maximize Capacity

•Adapt binary tree to JPEG

•Include run/size info

•Intelligently select which bit to watermark

•Improved Security

Additional Components

Michael Marcinak

Watermarking Part 2: Future Work

•Goals:

•Apply watermark algorithm to video

Video Applications

Michael Marcinak

Watermarking Part 2: Future Work

•Real-time

•Lossless

•Preserved filesize

•Format compliant

Video Applications

Michael Marcinak

Watermarking Part 2: Future Work

•Unlike JPEG, VLC tables may not be complete

Video VLC Codespace

Michael Marcinak

Watermarking Part 2: Future Work

•Problem:

•By introducing a watermark into the bitstream, an unaware decoder may interpret bit errors

•Solution:

•Exploit error resiliency of various standards

Watermarking Video

Michael Marcinak

Watermarking Part 2: Future Work

•Error propagation

•Error concealment (decoder)

•Error-resilient coding (encoder)

•Error resilient techniques in current standards

Error Resiliency

Michael Marcinak

Watermarking Part 2: Future Work

•Bit errors usually result in loss of information between resynchronization markers

Error Propagation

Michael Marcinak

Watermarking Part 2: Future Work

•Way of covering up corrupted data

•Three types:

•Spatial Interpolation - pixel blocks

•Temporal Interpolation - motion vectors

•Motion Compensated Temporal Prediction

Error Concealment

Michael Marcinak

Watermarking Part 2: Future Work

•Inserting Resynchronization Markers

•Data Partitioning

•Reversible Variable Length Codes (RVLC)

Error-resilient Coding

Michael Marcinak

Watermarking Part 2: Future Work

•Properties:

•Uniquely distinguishable from other codewords

•Intelligent placement - frames, slices, GOB

•Usually long length

•Enables decoder to regain synchronization

•Reduces coding efficiencyMichael Marcinak

Inserting Resync Markers

Watermarking Part 2: Future Work

•Partition MB header, motion vectors, and DCT information separately

•Limits error propagation

•Separate watermarking MV and DCT information

Michael Marcinak

Data Partitioning

•RVLC’s are uniquely decodable both forwards and backwards

•Longer than regular VLC’s

•Recovers more data

•Reduces compression efficiency

Watermarking Part 2: Future Work

Michael Marcinak

Reversible Variable Length Codes

Watermarking Part 2: Future Work

•MPEG 1/2 (MPEG 1991/1994)

•H.263 (VCEG 1998)

•MPEG 4 - Part 2 (MPEG 1999)

•H.264 (Advanced Video Coding) (JVT 2001)

Michael Marcinak

Video Standards

Watermarking Part 2: Future Work

Michael Marcinak

Comparison

ResyncMarkers

Data Partitioning

RVLC

MPEG 1/2 yes no yes

H.263 yes yes yes

MPEG 4 yes yes yes

H.264 yes yes no

Watermarking Part 2: Future Work

1. G. Cote, F. Kossentini, S. Wenger, “Error resilience Coding” in M. T. Sun, and A. Reibman, “Compressed Video over Networks” Marcel Dekker, 2000.

2. B. Girod, “Error-resilient Video”, Image, Video, and Multimedia Systems Group.

3. Li and Drew, “Fundamentals of Multimedia”, Prentice Hall, 2003.

4. D. P. K. Lun, “Error Resilient Coding Techniques”, Internet Technology for Multimedia Applications, 2002.

5. Y. Wang, S. Wenger, J. Wen, and A. Katsaggelos, “Review of Error Resilient Coding Techniques for Real-Time Video Communications”, Signal Processing Magazine.

6. S. Wenger et. al., “Error Resilience Support in H.263+”, IEEE Trans. CSVT 1998.

7. The International Telegraph and Telephone Consultative Committee, “Information Technology - Digital Compression and Coding of Continuous-Tone Still Images - Requirements and Guidelines”. CCITT Recommendation T.81, September 1992.

8. Telecommunication Standardization Sector of ITU, “Video coding for low bit rate communication”. ITU-T Recommendation H.263, February 1998.

References

Michael Marcinak